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Modern fire-rescue turntable ladders are constructed in a lightweight mode to increase their maximum operation velocities, maximum length, and outreach respectively. Hence, the ladder has a limited stiffness and will be more and more subject to oscillations of deflection along with dominant overtones. This paper deals with the active oscillation damping of such ladders. A new feedforward and feedback control strategy is applied. The feedforward control is calculated through system inversion of a multi-body system utilizing its differentially flatness. The design of the feedback is based on partial differential equations (PDE) describing a Euler– Bernoulli model of a beam with a concentrated point mass at the end. The modal representation of the system is constructed based on the analytical form of the eigenfunctions. For active oscillation damping by feedback without a dynamical observer the ladder was equipped with a gyroscope additionally to strain gauges. Due to computational efforts and measurement noise a reduced state vector is disposed for stabilization. The proposed control approach allows damping the fundamental oscillation as well as the first dominant overtone and asymptotically stabilizing the system around the reference trajectory. Measurement results from the IVECO DLK 55 CS fire-rescue turntable ladder validate the good performance of the control.

This paper deals with distributed parameter systems being described by inhomogeneous parabolic partial differential equations in one space dimension with a distributed control. The distributed control is presented by the right part of an equation, i.e. the source function. The source function can depend on the time as well as spatial variable. The approach for design of a feedforward control for the purpose of exact output tracking is presented. The design of the feedforward control is based on the examination of inverse system dynamics. The proposed technique utilizes the method of the variables separation and the representation of a solution by the power series in the time domain. Some examples and numerical simulations are included and demonstrate the efficiency of the proposed approach for developing the feedforward control.

In the paper the two degree of freedom control for a glass feeder is considered. The mathematical model of the plant is described by a time-varying partial differential equation in one space dimension with a source function corresponding to the control input. The control output is the temperature at the end of the feeder. The boundary input being an entrance temperature of the glass smelt is treated as a disturbance. The proposed strategy decouples approximately the control output from the boundary input as well as from the influence of the time-varying mass flow. The design of the control strategy is based on the system description with power series and flatness property. This description allows to develop the feedforward control and the decoupling part of the feedback. The stability of the closed loop system is analysed with the Lyapunov method. Some experimental results are shown and demonstrate the efficiency of the proposed control strategy.

This paper deals with the control of heat and mass transfer processes. The mathematical model of these processes is presented by a distributed parameter system with a so called distributed control and described by an inhomogeneous parabolic partial differential equation in one space dimension. The actuators in these processes are located above the channel, through that the medium to be heated flows. The distributed control corresponding to the actuators in the one-dimensional mathematical model is presented by the right part of the equation, i.e. the source function. The approaches for design of the feedforward and feedback control for the purpose of exact output tracking are presented. The design of the feedforward control is based on the flatness approach and examination of an inverse system dynamics. The proposed technique utilizes the method of the solution representation by power series in the time domain. The design of the feedback control is based on the utilization of generalized PI-control providing robustness. Some numerical simulations are included and demonstrate the efficiency of the proposed approaches.

In glass industry, the energy for the manufacturing process plays an important role for the productivity of the plant. Till now, the process is mainly controlled based on experience of the operators. In the paper a method is presented for deriving optimized feedforward control strategies resulting in reference temperature profiles for the plant control. Therefore a dynamic model based on partial differential equation as an approximation for the glass feeder gate is derived. Measurements show a good agreement to the simulation model behavior. Next step is the development of a feedforward control based on an approach via a flat system description in combination with optimization techniques. The obtained result was an advantageous temperature profile, which leads to a reduction of gas consumption at the plant of approximately 6 to 8 %.

This work deals with a heat transfer process and an optimal control of an inhomogeneous partial differential equation describing this process. One considers a glass feeder gate, which is present at many glass manufacturers. The use of the offered study is a development of an optimal feedforward control for dynamic behavior of this heating process. A mathematical model of the glass feeder gate is presented by a nonlinear distributed parameter system. The control design is based on approaches of a flatness description of dynamic systems and a parameterization of a reference trajectory for the optimization of the dynamical behaviour. The control strategy must be sufficient for a number of requirements to process (e.g. output temperature at the end of the feeder gate) and must provide optimum quality criteria (consumption of power). Some simulation results are included and demonstrate the efficiency of the control.